I know banjo is the topic here, but that jawbone is a really interesting (wierd) accompaniment instrument. I could see but couldn't hear Tim playing one on the Gettysburg videos, and a search turned up this YouTube video where it's a lot more audible: https://www.youtube.com/watch?v=jKo-L9HfUtw
Is it always a mule or horse's jaw? Was it used to accompany other instrument combinations, e.g., brass bands or pianos?
Are there any players here willing to post a jawbone demonstration video? I'd like to hear the range of effects you can get with one solo.... and I don't imagine anyone will be establishing a jawbonemusic.ning.com network....